Tev Observations of the Variability and Spectrum of Markarian 421
Astrophysics
2007-05-23 v1
Abstract
Markarian 421 was the first extragalactic source to be detected with high statistical certainty at TeV energies. The Whipple Observatory gamma-ray telescope has been used to observe the Active Galactic Nucleus, Markarian 421 in 1996 and 1997. The rapid variability observed in TeV gamma rays in previous years is confirmed. Doubling times as short as 15 minutes are reported with flux levels reaching 15 photons per minute. The TeV energy spectrum is derived using two independent methods. The implications for the intergalactic infra-red medium of an observed unbroken power law spectrum up to energies of 5 TeV is discussed.
Cite
@article{arxiv.astro-ph/9706125,
title = {Tev Observations of the Variability and Spectrum of Markarian 421},
author = {J. E. McEnery and I. H. Bond and P. J. Boyle and S. M. Bradbury and A. C. Breslin and J. H. Buckley and A. M. Burdett and J. Bussons~Gordo and D. A. Carter-Lewis and M. Catanese and M. F. Cawley and D. J . Fegan and J. P. Finley and J. Gaidos and A. Hall and A. M. Hillas and F. Krennrich and R. C. Lamb and R. W. Lessard and C. Masterson and G. Mohanty and P. Moriarty and J. Quinn and A. J. Rodgers and H. J . Rose and F. W. Samuelson and G. H. Sembroski and R. Srinivasan and T. C. Weekes and J. Zweerink},
journal= {arXiv preprint arXiv:astro-ph/9706125},
year = {2007}
}
Comments
4 pages, 4 figures, to appear in proceedings of 25 ICRC (Durban)